tokenization-utilnpm
tokenization-util is a confirmed malicious npm package (MAL-2026-6440) that steals credentials and exfiltrates sensitive data (malicious versions 0.1.0, 0.2.0, 1.1.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in tokenization-util (npm)
What this malware does
The package advertises plain math/formatter helpers but index.js contains a heavily obfuscated payload concealed inside the calculateTokenPrice function. The payload is hidden behind ~1500 leading tab characters of visual padding, then uses two seeded Fisher-Yates string-shuffler decoders and String.fromCharCode splicing to reconstruct the identifiers 'constructor', 'require', and 'module' at runtime. The code resolves Function via yLb[kqz] (a string-shuffled property lookup for 'constructor'), uses that Function constructor to build a decoder from one shuffled blob, decodes a second scrambled blob into JS source, and invokes that source via Function(...)(3004). It also assigns the CommonJS require and module bindings to globalThis (global[require]=require; global[module]=module), giving the decoded code access to any Node built-in (network, fs, child_process) regardless of how the package is imported. None of this behavior is documented in the README or exposed through the advertised API. The combination of multi-layer obfuscation, visual concealment via tab padding, dynamic eval of decoded literals, and forced global exposure of require/module is the canonical shape of a hidden remote-code-execution backdoor in an npm utility package — the decoded payload runs whenever calculateTokenPrice is called by a consumer.
Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for tokenization-util (3 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging tokenization-util across your stack and pipelines.
If you installed it — respond
tokenization-util is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If tokenization-util was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks tokenization-util before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks tokenization-util-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.